John Dory

This stock is severely data-limited, with no formal stock assessment for over 10 years. There is concern for the biomass but no concern for fishing pressure.Little is known about John dory. It is a widely distributed species throughout the world, but there are no formal stock assessments or management measures in place. In at least one part of its range, off Mauritania, the species experienced a rate of decrease in biomass of 7% annually over a period of 24 years. It continues to be heavily exploited off Mauritania. In the UK, however, a 2011 report assessed it as an 'underutilised' species.While there is no information about the status of the stock, in the UK there is no targeted fishery for this species, and it is only caught as unavoidable bycatch. As long as this remains the case, MCS considers that fishing pressure is not of concern. This species has medium resilience to fishing pressure.John Dory is generally found shallower than 200m, and shows preference for warmer temperatures. Consequently, it is considered a climate change 'winner', with increasing sea temperatures resulting in more suitable habitat being available. Their distributions are shifting northwards and fishers have recently seen more of more of them in the North Sea.This is not a targeted species, occurring instead as bycatch in demersal fisheries. FAO data indicates that catches of this species in the North East Atlantic (NEA) peaked in 2010 at 5,100 tonnes and then declined to 3,131t in 2016 - the lowest catch since 2002. According to the Marine Management Organisation (MMO), 229 tonnes of John Dory were landed by UK vessels in 2020, about half of which was caught in the western English Channel. Most of the rest was caught to the west of that, in the Bristol Channel, Celtic Sea and south and west of Ireland. It is possible that the fish in these areas constitute one stock, with another off the Iberian coast, but stock structure is unknown. Over 75% of the catch in 2020 was by otter trawl, and most of the rest (around 12%) by beam trawl. As with the wider North East Atlantic fishery, recent UK catches have declined (from 308 tonnes in 2014). This could be caused by a number of factors.

There are no management measures in place, and therefore the stock is not protected from overfishing. There is too little scientific evidence to inform effective management, even if measures were to be developed.In the English Channel, the mean length of first maturity has been estimated at 26cm in males and 34.5cm in females - around age 5. This species is usually solitary and spawns in the spring in the northeast Atlantic. It is a demersal species, and feeds on a variety of fish, cephalopods and crustaceans.Both the EU and UK have fishery management measures in place, which can include catch limits, targets for population sizes and fishing mortality, and controls on what fishing gear can be used and where. In the EU, compliance with regulations has been variable, and there are ongoing challenges with implementing some of them. There was a target for fishing to be at Maximum Sustainable Yield by 2020, but this was not achieved. The Landing Obligation (LO), an EU law that the UK has kept after Brexit, requires all quota fish to be landed, even if they are unwanted (over-quota or below minimum size). It aims to promote more selective fishing methods, reduce bycatch, and improve recording of everything that is caught, not just what is wanted. Compliance with the LO is generally poor and actual levels of discards are difficult to quantify using the current fisheries observer programme. UK administrations are in the process of replacing the landing obligation with country-specific Catching Policies.In the UK, it is too early to tell how effective management is, as the Fisheries Act only came into force in January 2021. The Act requires the development of Fisheries Management Plans (FMPs) (replacing EU Multi-Annual Plans). FMPs are currently in development, but the scope of them remains unclear. They have the potential to be very important tools for managing UK fisheries, although data limitations may delay them for some stocks. MCS is keen to see publicly available FMPs for all commercially exploited stocks, especially where stocks are depleted, that include:Targets for fishing pressure and biomass, and additional management when those targets are not being met, based on the best available scientific evidenceTimeframes for stock recoveryImproved data collection, transparency and accountability, supported by technologies such as Remote Electronic Monitoring (REM)Consideration of wider environmental impacts of the fisheryFor more information about this fishery in Cornwall, see: http://www.cornwallgoodseafoodguide.org.uk/fish-guide/john-dory.php

Over 75% of John Dory in the North East Atlantic are caught by otter trawls, which are likely to cause some damage to the seabed. Bycatch in otter trawling is moderate and may include some vulnerable species.John Dory are normally taken as bycatch in mixed demersal fisheries targeting hake, anglerfish and megrim.Demersal otter trawls have the potential to take relatively high quantities of bycatch. In the North East Atlantic there are reported catches of demersal elasmobranchs and endangered, threatened and protected (ETP) species, such as sharks, rays and marine mammals. Bycatch data is limited in many UK and EU fisheries as they are generally not well monitored.John Dory live on soft and muddy substrates, close to rocks. Demersal trawls have contact with the seabed, resulting in penetration and abrasion of habitat features. The impact of trawling on the seabed depends on the location and scale in which trawling occurs. For example, areas that are used to natural disturbance through tides and waves, are less sensitive to habitat impacts. Areas not used to mobile towed gears are typically more sensitive to trawling. Trawl gears are known to have some of the greatest impacts on Vulnerable Marine Ecosystems (VMEs).To mitigate the impact of capture of the species, rockhoppers are advised on bottom trawling gear. Due to John Dory's unusual shape, few gear adaptations can feasibly be implemented to increase selectivity. There are general adaptations used in the fishery on beam trawl, demersal trawl and gill nets, though these are not specific to the species.There are Marine Protected Areas (MPAs) in this area, some of which are designated to protect seabed features from damaging activities. This fishery overlaps with parts of these MPAs, but the proportion of the catch coming from these areas is expected to be relatively low in relation to the unit of assessment (i.e. less than 20% of the catch or effort), and so these impacts have not been assessed within the scale of this rating. Given the important role that MPAs have in recovering the health and function of our seas, MCS encourages the supply chain to identify if their specific sources are being caught from within MPAs. If sources are suspected of coming from within designated and managed MPAs, MCS advises businesses to establish if the fishing activity is operating legally inside a designated and managed MPA, and request evidence from the fishery or managing authority to demonstrate that the activity is not damaging to protected features or a threat to the conservation objectives of the site(s).To improve monitoring and reporting of fishing activity, MCS would like to see remote electronic monitoring (REM) with cameras implemented, used and enforced. To reduce the impacts of fishing on the marine environment we would like to see a just transition to the complete removal of bottom towed gear from offshore Marine Protected Areas designated to protect the seabed. We also want to see reduction and mitigation of environmental impacts including emissions and blue carbon habitat damage.

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